Although we don't believe in timing the market or panicking over daily movements, we do like to keep an eye on market changes -- just in case they're material to our investing thesis.

Stocks largely continued their downbeat 2014 today, with the Dow losing 68 points even as the S&P finished almost unchanged and the Nasdaq gained ground. Even the Federal Reserve's latest minutes weren't enough to convince many investors to get more optimistic about the market, and poor performances from J.C. Penney (JCPN.Q), Ambarella (AMBA -1.87%), and Container Store Group (TCS -3.54%) didn't help to inspire nervous investors to recommit to stocks.

J.C. Penney fell 10% after investors demanded more information before accepting the struggling retailer's assertion that it was "pleased with its performance for the holiday period." Even though the company's reiteration of guidance promised improvement in same-store sales and gross margins, investors were unhappy that Penney didn't choose to highlight any particular successes during the holiday quarter. Given the company's ongoing difficulties, many investors likely fear that Penney stayed mum because there weren't any notable success stories to report.

Ambarella declined 9% on an analyst downgrade, giving back a small portion of its 80% gains over the past two months. The maker of high-definition video chips and products came out with a camera product for use in automobiles that it highlighted at the Las Vegas Consumer Electronic Show, and Ambarella has plenty of other opportunities for innovations including wearable cameras and other video products. After such an impressive gain, though, analysts at Needham concluded that the stock had come too far too fast, downgrading Ambarella to hold.

Container Store Group dropped 15% after announcing its quarterly results, which included revenue gains of 7.3% led by same-store sales gains of 4.7%. Improving gross margins and a rise in average transaction amounts were also positive, but investors worried about a drop in traffic, and a lower forecast for same-store sales going forward led some investors to be more circumspect about the stock after its 26% rise between the end of its first trading day in early November and its close yesterday. Even after the drop, the stock still trades above that Nov. 1 close, let alone its $18 offering price.